I did my first real ride yesterday, about 85 miles mixed freeway, secondary and gravel/dirt roads. I noticed a slight difference in the on road handling, the bike seems to turn in a bit slower and the Heidenau I'm running wants to follow rain grooves and tar snakes. Also not quite as stable at freeway speeds. In the gravel and dirt however, wow. Confidence inspiring is the phrase. Being the weekend before Christmas I didn't have time for a long ride but I can't wait to to an extended back country trip and see how the work. If your on the fence about a 21" conversion, just do it. The on road compromises are completely worth the improvement in off road ability.